Controlling device for the keys of keyboard machines



Nov. 6, 1928.

P. M. COLQUHOUN CONTROLLING DEVICE FOR THE KEYS OF KEY BOARD MACHINES 4Sheets-Sheet 1 Quads r022 dew T Filed March 9, 1925 Nov. 6, 1928.1,690,443

P. M. COLQUHOUN CONTROLLING DEVICE FOR THE KEYS OF KEY BOARD MACHINESFiled March 9, 1925 4 Sheets-Sheet 2 Nov. 6, 1928.

P. M. COLQUHOUN CONTROLLING DEVICE FOR THE xms OF KEY BOARD MACHINESFiled March 9, 1925 4 Sheets-Sheet 3 Nov. 6, 1928. 1,690,443

r I P. M. COLQUHOUN CONTROLLING DEVICE FOR THE KEYS OF KEY BOARDMACHINES LVZIVZQZB 72 15 M fiz'z'oreA/zza 20 raised rear end of thedepressed Patented Nov. 6, 1928.

"UNITED STATES 1,690,443 PATENT OFFICE.

PETER I. COLQUHOUN, OF CLEVELAND, OHIO, ASSIGNOR TO THE AMERICAN MULTI-GRAPH COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

CONTROLLING DEVICE FOR THE-KEYS OF KEYBOARD MACHINES.

Application filed March a, 1925. Serial No. 14,118.

machine which has matured into Patent 1,557,7 54 dated Oct. 20, 1925shows,-describes and claims a machine for embossing a row of charactersupon a printing strip or ribbon comprising a reci rocating die headhaving male and fema e dies facing each other on opposite sides of theribbon, a keyboard to control the position of the die head,

a plunger mechanism operating automatically when the die head comes toposition to force the selected dies toward each other to cmboss the.ribbon. The keys are arranged l in two banks, and each key of a bank isadapted to energize a mechanism associated with that bank and serving tomove the die head from a central neutral position in one.

ging the ey lever. Consequent upon such engagement the auto maticmechanism is initiated which plunges the dies toward each other;

Means is provided in the Chisholm ma- 2 chine to prevent the depressionof a subsequent key until the preceding key has been released andreturned to'normal position, but is has. been found that ocassionallyafter the embossing operation is completed, and the depressed keyreturned, the operator direction until it is stopped by en will strike asecond keyin the same bankv before the die head has had time to returnto neutral position, with the result that the die head is stopped on thereturn stroke instead of on a second outward stroke and that the wrongcharacter is embossed. This result happens especially when the first keystruck is one which gives the die carrier nearly its extreme movementand the second key happens tobc one which would give the die carrieronlya short movement, that is to say where there is considerable s aceinterval between the rear end of the rst depressed key and that of thesecond key, and

even then it only happens when the operator is actuating the-keys in thesame bank in very rapid succession. 1

The difliculty mentioned may be'avoided by care on the part of theoperator, but a an speedier operation may be obtained if the operatordoes ngt have to pay attention to this contingency. It is the object ofthe present invention to provide -mechanism to positively preventtheactuation of a second key in the same bank until the die head hasreturned to its neutral position.

The present invention provides means preventing the actuation not onlyof a subsequent character key in the same bank, but also of the spacekeyuntil the die head is returned to neutral position. In the Chisholmmachine, the space key, while it does not operate" to shift the diehead, does operate the plunger mechanism, because the ribbon feedingmechanism is coupled therewith, and hence the space key, if operated tooquickly after a positioning key may cause the plungers to engage dies asthe die head is returning instead of operating in a vacant space at thecenter of the die head. The peculiarity of the Chisholm space keymechanism requires a different mechanism for preventing this actuationfrom that of a character key and the present invention provides suchdifierent mechanism.

My invention is illustrated in the drawings hereof and is hereinaftermore fully explained. Its essential characteristics, however, which areset out in the claims, are not intended .to be limited to the specificmechanisms shown.

In the drawings, Fig. 1 is a sectional side 1 ing also my safetymechanism; Fig. 2 is a section plan indicated by the line 2-2 on Fig. 1of the relevant portion of the embossing machine shown in Fig. 1; Fig. 3is a vertical cross-section of the offset planes indicated by the lines3-3 in Figs. 1 and 2 looking-toward the rear; Fig. 4 is a cross sectionon the line on Fig. 1 looking toward the front; Fig. 5 is a detail inver tical section on the plane indicated by the line 55 on Fig. 2showing my safety mechanism in active position; Fig. 6 isa fra mentaryside elevation illustrating the re ative position of parts of my safetymechanism after a key has been returned to normal position but beforethe die head has returned.

I will first describe so much of the Chisholm machine as is concernedwith my invention. The frame of the machine comprises a bed plate 10 andnumerous standchine above an extension of the bed plate .solenoidmagnets becomes and consists of suitable finger pieces 20 havingrearwardly extending levers 21. At the rear of the keylevers is thereciprocating die head 30 mounted to move laterally in either directionfrom a central position of rest and carrying die blocks 40 and 41 incooperating pairs slidable toward and from each other and havingrespectively male and female dies on their adjacent ends.

Near the rear of the machine are two solenoid magnets (one of which isshown at 60) which operate a common core bar 61 connected by a linkagesystem 62 with the die head. Above each bank of key levers is ahorizontal rod 65, each of which is carried by the rear end of anintermediately pivoted lever 66. The forward end of each lever carries adownwardly extending rod 67, which when depressed closesa pair ofcontacts 68 forming the terminals of a circuit to the correspondingsolenoid magnet.

It results from the mechanism just described, that when a key in theright hand bank is depressed the corresponding circuit is closed toenergize that magnet, which pulls the die head toward the right untillatch mechanism carried therewith engages the rear end of the actuatedkey lever. Simi larly when any key in the left hand bank is depressed,the adjacent lever 66 closes the circuit through the other solenoid maet which draws the die head toward the left.

The die head when moved by one of the automatically locked in itsselected position by means of a latch movable with the die head. Thislatch comprises a traveling block or carria e 70 which carries a pair ofplungers 71 wit inclined lower faces, and a pair 'of abutments 72, eachcomprising an L-shaped. end on a bar-73, slidably mounted in the blockand restrained agalnst inward movement by a compression spring 74.Accordingly, as the carriage approaches a raised key lever, the beveledlower face ,of the plunger 71 rides over the top edge of the key leverand dro s beyond it, then the abutment en ages the side of the keylever. The spring a lows a slight further movement of the carriage,whereby the same is gently brought to rest, the spring then pushing thecarriage so that the same is held accurately in place with the abutmenton one side of the raised key lever and the plunger on the other side.

The dies 40 and 41 preferably each have a plurality of characters ontheir faces and either horizontalrow of characters is selected by movingthe die head vertically, by a shift mechanism, not shown. The die headis shown as equipped with rollers 31 which ride on a horizontal guidebar 33 which is normally stationary but may be raised by shift mechanismto determinewhich face of the dies shall be opposite the intermediatestrip to be embossed. On account of this shift movement of the die head,the latch carriage 70 which travels horizontally with the die head isindependent as far as vertical movement of the latter is concerned. Thisis effected by guiding the carriage by rollers 75 extending into ahorizontal channel shaped frame member 76, while a vertical gib 77connects the carriage with the die head.

The die head rides on the shiftable bar 33 mentioned and has also arearward portion 35 around a stationary bar 36 upon which are a pair ofcompression springs 37 tending to center the die head. The die head isalso provided with rollers 39 hearing on opposite faces of the framebars 110 and 111. The dies 40 and 41 are preferably held in withdrawnposition by the fingers of springs 43 carried by brackets 44 on the diehead. The drawings also show a pair of sheering dies 46 and 47 operatingto cut oil the embossed'portion of the ribbon.

In front of the die head and in the rear thereof located centrally ofthe machine are pairs of plungers 80 which are adapted to be engaged byabutment pins 81 on a pair of pivoted vertical levers 82 and 88, thelower ends of these levers carry rollers 83 engaging double crown cams84 on a shaft 85. This shaft is adapted to be connected by a cllutch 96with a continuously driven pulley 9 Overlying the plungers 71 is apivoted bail 90 which is connected by a link 91 to a hell crank 92 whichoperates a rod 93 extending in front of and normally stopping a member98 of the clutch. The clutch rod 93 is normally drawn into operativeposition by the spring 95.

It results from the above described mechanism, that whenever the diehead comes to osition, the corresponding plunger 71 rising romengagement with the key lever raises the bail 90, pulls up on the link91, swings the bell crank 92 and withdraws the rod 93 from the clutch,thereupon the clutch goes into engagement and the power rotates theshaft which through the cams and levers, forces inwardly the twoplungers 80. The selected dies at that time are directly between theseplungers and thus are caused to emboss the interposed ribbon.

The ribbon as shown at A, is originally a flat strip of metal comingfrom a reel (not shown) and passing between a pair of feed rollers, oneof which is shown in Fig. 3 at 100. These rollers are periodicallyactuated to feed the strip a distance of one character and at the sametime flange the edges of it to give it a channel shape. Such channelshaped ribbon is guided by a horizontal rib on the lower portion of theframe plate 110 and the adjacent face of the cooperating frame plate111. These frame plates are cut away directly between the plungers 80 sothat the positioned dies may move through this gap and emboss theribbon.

The forwardembossing lever 88 is rigidly mounted on a rock shaft 89, andthis shaft,

carries at its end a rock arm 101 which is connected with a levercarrying a pawl 102 operating a ratchet 103 on the shaft 104 of theribbon advancing roller 100. Thus, on the back stroke of the embossinglevers, the ribbon is advanced one character space.

\Vhen the space key is actuated, it is necessary to advance the ribbonbut not necessary to move the die head. Accordingly, in the Chisholmmachine, the space given key 120 carries a latch 121 which engages withthe bell crank 92 and swings it to withdraw the rod 93 from the clutch,causing the embossing levers to swing. At this time, the plungers areopposite a clear space between the dies in the die head which are in twogroups as shown in Fig. 3, so that no embossing action takes place. Onthe return stroke of the embossing arms the rock shaft 89 of the arm 88through the mechanism described feeds the ribbon.

To lock the die head normally in its central position, the Chisholmmachine provides a pair of levers 130, each of which carries at itsupper end a horizontal bar 131 behind the die head and at its lower enda universal bar 132 overlapping the rear ends of the key levers of thecorresponding bank. The die head carries a vertical gib 135 which liesnormally between the bars 131 of the two center lock levers. Now, when akey is depressed in the right hand bank, the corresponding bar 131 iswithdrawn from engagement with the die head and it is allowed to movetoward the right, and the corresponding action toward the left handtakes place when a key in the left bank is depressed. When the keyactuated returns to normal position following the embossing operation,the die head travels back to position with its gib sliding along theface of the bar 131 on that side and comes to rest as this gib clearsthat bar 131 and engages the end of the other bar 131, thereupon thereleased bar swings forward into place by-means of a spring 136connected to a pin 137 on the lever and the die head is locked incentral position. The rearward limit of the stroke movement iscontrolled by the adjustable stop 138, Fig. 1.

As soon as a key is depressed, the elevated rear end is retained in thatposition by means of the universal hooked bar 140 swung by a spring 141so that it engages beneath a tooth 23 on the key lever and this rear endremains elevated until after the embossing is completed. On the returnstroke of the forward embossing lever 88, a latch member 142 thereonengages the upper end of a rocking member 143 which carries theuniversal bar 140 and withdraws it from the tooth 23 and at the sametime an arm 145 projecting from this rocking member engages the rod andforces it downwardly, depressing the raised rear end of the key lever,bringing the latter to normal position.

Beneath the key levers is a transverse train of balls 150 having anaggregate available clearance only slightly greater than the width ofone key lever, with the result that whenever any key lever is depressedno other key lever may be depressed until the I first lever has returnedto normal position. The same frame member which supports the train ofballs may carry a transverse rod 152 on which springs 153 tending toraise the key levers are anchored.

It will be seen after the return of the key lever to normal position,there is a slight interval before the die head reaches its centralposition and it is during this interval that occasionally a very rapidoperator has struck a second key in the operation of the Chisholmmachine before the die head returned to position. As heretofore stated,it is the object of my invention to prevent striking a second key in thesame bank during this interval, and it has been necessary to give thisdescription of the Chisholm machine in order that my mechanism,preventing such inadvertent operation which will now be described, maybe readily understood.

As heretofore explained, the rocking lever 66 which was swung (forwardend down and rear end up) whenever a key in the associated bank wasdepressed is returned to initial position at the completion of theembossing stroke by reason of the withdrawal of the latch 140 from thekey tooth 23, by the arm 145 engaging the rod 65 and the spring 69acting upwardly on the forward end of the lever. My attachment includesa rearwardly extending bar 160 rigidly secured to the lever 66 andcarrying near its rear end a slidable'latch dog 161 mounted in a doublearm bracket 162 on the lever 160 and pressed toward the rear by a spring163. This latch dog cooperates with a downwardly extending arm 165 rigidon the end of the rock shaft 166 on whichthe corresponding center locklever 130 is mounted.

It will be noticed that there is some clearance between the underface ofthe overhanging flange of the universal bar 132 and the upper edge'ofthe rear ends of the key levers. When a key is struck, the latch dog 161rises during the slight interval while this clearance is being taken upsufficiently to stand in front of the arm 165, and thereafter as the keylever movement continues the arm 165 bearing against the latch. dogpresses it forwardlv so that the parts come into the position shown inFig. 5. Now, as. soon as the forward'embossing lever 88 returns to itsinitial position following the embossing stroke and thereby releases thekey which was active and. results in the return of the lever 66, the bar160 is swung down to normal position, whereupon the latch dog 161springs beneath the forwardly overhanging arm 165 as shown in Fig. 6.

The arm 165 is held in the position shown in Fig. 6, by the rearwardcanting of the lever 130 by reason of the die head engaging the centerlock bar 131. So long as the center lock lever retains this position, nokey may be depressed for the arm 165 standing over the latch dog holdsthe bar 160 down and thereby holds the lever 66 with its rod holdingdown the keys of that bank. Soon after the die head returns to centralposition, the spring 136, acting on the center lock lever returns it tonormal position, which causes the arm 165-to clear the latch do, theparts thus coming in position shown in ig. 1. This frees the keys foraction.

It will be seen that the mechanism above described prevents theactuation of any subsequent character key after an actuated key of thatbank has been released until the die head has reached its centralneutral position. It will be remembered that the Chisholm machine isprovided with means preventing the actuation of more than one key at atime, and accordingly the difiiculty cured by my mechanism arises onlyif a key is struck during that very ,short interval which exists betweenthe return of one key and the return of the die head to neutralposition.

When the Chishohn machine is equipped with my mechanism there is nodanger of the operator inadvertently pressing a second key too quicklyafter the release of the first key. The operator may accordingly operateat the maximum speed, and when he finds a key locked he simply retainshis finger thereon during the short time that elapses until the key willrespond to his pressure.

I have described the operation of the latch dog with reference to theleft hand bank of keys. It is to be understood that another one of thesearms 160 on the other side of the machine is secured to the other lever66 and operates on the other center lock lever, in the manner alreadydescribed, as illustrated by Fig. 2.

Since the space key does not actuate either of the levers 66, I providean additional bar 170, pivoted on the same center as the'leveis 66 anddrawn by a spring 171 against the undersideof the space key lever. Thisbar 17 0 extends rearwardly to a position which is normally just infront of the center lock arm 165 and just beneath the plane of its loweredge. Now, whenever the die head is out of neutral position, the arm 165overhangs the bar 170 as shown in Fig. 5, and the space key cannot beactuated. As soon however, after the die head has returned to centralposition, the arm 165 is withdrawn from above this bar 170 as shown inFi 1, and the space key is free for action. his mechanism accordinglyrevents inadvertent actuation of the s ace liey during that intervalwhen such ey is otherwise released, and. when its actuation might resultin the plungers engaging the dies and effecting improper embosslng andperhaps injury to the dies or plun ers.

It should c noticed that my mechanisms preventing actuation of a subseuent key apply to the two banks indepen ently, so that the actuation ofthe key in one bank does not prevent a ke in the other bank beingactuated immedlately after the first key is released. This ispermissible since such other key necessarily acts on the die head afterit has returned to its central osition of rest and passes beyond thatposition in the other direction. Accordingly, it is immaterial if theoperator presses the ke in the other bank after the first key has eenpressed and before the die head has returned. My locking mechanism doesnot delay the actuaton during such interval.

Having thus described my invention, I claim:

1. In an embossing machine having a cycle of operations initiated by theactuation of a key, the combination of a keyboard, a set of dies, meansfor holdin material to be embossed thereby, there hang a neutralposition of the dies relative to said material, means for changing andrestoring the juxtaposition of the dies and material, the keyboardhaving finger keys adapted to actuate the last mentioned means, meansfor restoring an actuating key before the cycle of operation is comp etcand means for preventing the actuation of a subsequent key, until theneutral position of the-dies relative to the material is restored.

2. In an embossing machine having a cycle of operations initiated by theactuation of a key, the combination of a keyboard having finger keys,male and female emboss'ng dies, means for holding material to beembossed, there being a normal position of rest of the dies andmaterial, means for changing the relative position of the dies andmaterial and for restoring such position under the control of anactuated finger key, means for locking such key, means for releasingsuch key before the cycle of operat'on is completed and means forpreventing the actuation of a subsequent key until the normal positionof the dies and material, relative to each other, has been restored.

3. In an embossing machine, the combination of a movable die headcarrying embossing dies and having a normal positon of rest, mechanismfor moving said die head from said normal position, a keyboard havingkeys for determining the position to which said de head is moved,mechanism for Ill bossing dies having a neutral position, a

keyboard, mechanism controlled thereby for positioning the die head,mechanlsm for antomatically operating a selected die conse- ,quent uponthe die head coming to position,

, means for locking an actuated key, means for releasing such actuatedkey, means for thereafter returning the die head to neutral position,and mechanism for preventing the actuation of a subsequent key until thedie head has returned to neutral position.

5. In an embossing machine having a cycle of operations initiated by theactuation of a key, the combination, with embossing mechanism, of akeyboard for controlling the same, means for restoring an actuated keybefore the cycle of operation is complete, and means for preventing theactuation of a subsequent key until a preceding key is restored, andmeans for preventing actuation of a subsequent key after a preceding keyis restored but before the cycle of the machine is completed.

6. In an embossing machine, the combination of a movable die head, aplurality of keys, mechanism control thereby to move the die head from aneutral position of rest and thereafter returning to such position,means for locking an actuated key, means for releasing such actuated keybefore the die head has returned. i

7. In an embossing machine having a cycle of operations initiated by theactuation of a key, the combination with a keyboard, of embossing diesactuated thereby, means for locking an actuatedkey until after theembossing action has taken place and then releasing it before the cycleof operation is complete, and means for preventing the action of asubsequent key during the interval between the release of the first keyand the completion of the cycle of operation.

8. In an embossing machine having a cycle of operations initiated by theactuation of a key, the combination with embossing dies, a plungermechanism for moving them,

a keyboard for causing coaction between the plunger mechanism andselected dies, means for locking an actuated key until after the plungermechanism has acted, and means for releasing an actuated key before thecycle of operation is complete.

9. In an embossing machine, the combination of a movable die carrierhaving a neutral position, means for moving the carrier from suchneutral position and means for returning it thereto, a plunger mechanismfor actuating the dies, a keyboard, mech anism actuated thereby andhaving a movement independent of the movement of the actuating key formoving the die carrier to the position determined by the key actuated,whereby dies corresponding to such key are caused to register with aplunger mechanism,

and means for locking the keyboard against subsequent actuation of a keyin that bank until the die head has returned to neutral position.

10. In an embossing machine, the combination of a reciprocating diecarrier having a position of rest, key actuated mechanism having amovement independent of the movement of the actuated key for moving thedie carrier intermittently from such position of rest,a keyboard havingsuch actuating keys controlling the position to which the die carrier ismoved, and means for look.- ing the keyboard against subsequentactuation of a key in that bank until the die head has returned toneutral position.

11. In an embossing machine having a cycle of operations initiated bythe actuation of a key, the combination of embossing dies,

a keyboard arranged in two banks, one bank controlling relative movementof the dies and material to be embossed in one direction andthe other inthe other direction, and means whereby, when any key has been actuated,no other key in that bank may be actuated until the cycle of operationis completed, means for locking an actuated key and means for releasingsuch actuated key in advance of the completion of the cycle ofoperation.

12. In an embossing machine having a cycle of operations initiated bythe actuation of a key, the combination of a reciprocating die headcarrying embossing dies, said die head having an intermediate positionof rest and being adapted to move in either direction therefrom,mechanism for so moving the die head, a keyboard arranged in two banks,one bank controlling movement in mechanism of a keyboard for controllingthe same, locking mechanism to hold theembossing mechanism in neutralposition, means whereby any of a plurality of keys may release suchlocking mechanism and means for restoring an actuated key in advance ofthe completion of the cycle of operation. 1

14. In an embossing machine, the combination of embossing dies, meansfor holdlock when the latter-is in its abnormal posi-' tion. I

15. In an embossin machine having a c cle of operations initiated by theactuation of a key, the combination of a movable die head, mechanismsfor moving it from a position of rest to various active positions andfor returning it therefrom, a lock for the die head, a plurality of keysany of which may release the lock and actuate the die head, means forrestoring an actuated key before the cycle of operation is complete, andmechanism. controlled by such lock to prevent the actuation of asubsequent key until the die head has returned.

16. In an embossing machine, the combination of a reciprocable die head,a lock adapted to hold it in neutral position, a plurality of keys anyof which may release the lock, and latch mechanism coacting with thelock preventing the actuation of a subsequent key until the lock hasreturned to locking position.

17. In an embossing machine, the combination of a reciprocable die head,a center lock adapted to hold it normally in central position, aplurality of keys in two banks, mechanism whereby any key in the bankmay release the center lock sufficiently to allow movement of the diehead in any direction, and mechanism coacting with the center lockpreventing actuation of a subsequent ky in the same bank until thecenter lock has returned to locking position.

18. The combination of a movable die carrier, a lock therefor, aplurality of keys any one of which may release the lock, a membermovable by any of said keys and having a latch dog coacting with lock ina manner not to interfere with the operation of thelock, and mechanismcontrolled by the latch dog for preventing the actuation of a subsequentkey until the lock is returned.

19. The combination of a movable die head having a position of rest, alock having a member adapted to hold thedie head in such position, akeyboard having keys cooperating with said member to move it to releasethe die head for movement, a spring pressed latching dog for said keys,means for moving it into abutting position with means carried by thelocking member whereby the spring is constrained as the key operation iscompleted, and means for moving said latch dog away from the lockingmember into a position where it is blocked thereby when the key isreturned.

20. The combination of a reciprocating die head having a centralposition of rest, a center lock havin a pair of members adapted to holdthe die head in such central position, a keyboard having keys arrangedin two banks, each bank cooperating with one of said members to move itto release the die head for movement in that direction, a spring pressedlatching dog for each bank of keys, means for moving it into abuttingposition with means carried by one of the center locking members wherebythe spring is constrained as the key operation is completed, and meansfor moving said latch dog away from the center lockin member into aposition where it is blocke thereby when the key is returned, therebyholdingall of the keys in that bank against subsequent movement untilthe center lock member is returned. a

21. The combination with a movable die head having embossing dies andhaving a normal position, a locking lever carrying a bar extendingparallel with the direction of movement of the die head and coactingwith the die head in its various positions other than its neutralosition, said locking member coacting wit a bank of keys whereby any keyin the bank may release said member, means for thereupon causingactuation of the die head along the released locking member whereby thelatter may not return to normal position until the die head has returnedto normal (position, and a. latching mechanism couple with the keys andcoactmg with such locking member and adapted to prevent the actuation ofa subsequent key until the locking lever has re turned to lockingposition.

22. The combination with a reciprocating die head having embossing dies,a air of center lock levers each carrying a ar extending parallel withthe'direction of movement of the die head and coacting with the die headin its various positions other than 1ts neutral position, each centerlock member overhanging a bank of keys whereby any key in the banks mayrelease its center lock member, means for thereupon causing actuation ofthe die head in contact with the bar of the released center lock memberwhereby the latter may not return to normal position until the die headhas returned to normal position, and a latching mechanism coupled withthe keys and coacting with such center lock member and adapted toprevent the actuation of a subsequent key until the center lock hasreturned to locking position.

23. In an embossing machine, the combination of a reciprocating die headhaving a central position of rest, the keyboard arranged in two banks,mechanisms actuated by keys in the respective banks for moving the diehead from the central position in one direction, mechanism for lockingit in a position determined by the key actuated, mechanism for theneffecting the embossing operation and releasing the key, a pair ofcenter lock levers each adapted to be actuated by any key in thecorresponding bank and serving to release the die head from its normalposition of rest for movement in one direction, means for preventing thereturn of the center lock lever until the die head has returned, and alatch mechanism operated by any key in the bank and coacting with thecenter lock mechanism to prevent the actuation of a second key in thatbank until the die head has returned.

24. In an embossing machine, the combination of a reciprocating die headhaving a central position of rest, the keyboard arranged in two banks,mechanisms actuated by keys in the res ective banks for moving the diehead rom the central position in one direction, mechanism for locking itin a position determined by the key actuated, mechanism for thenefiecting the embossing operation and releasing the key, a pair ofcenter lock members each adapted to be actuated by any key in thecorresponding bank and serving to release the die head from its normalposition of rest for movement-in one direction, means for preventing thereturn of the center lock member until the die head has returned, and alatch mechanism comprising a spring pressed latching dog on a barmovable with any key lever of that bank, and coacting with an armmovable with the corresponding center lock member, said latching doghaving its spring constrained when the center lock is released, andmechanism for releasing an actuated key and returning the dog to aposition where it is blocked by the center lock whereby subsequentactuation of a key is restrained.

, 25; The combination of a reciprocating die head having a normalposition, character keys for controlling the movement of the die carrierfrom its normal sition, mechanism initiated by such keys or moving thedies to effect the embossmg, a space key which feeds the materialwithout causing embossing, mechanism for returning the die head tonormal position and mechanism for preventing the actuation of the spacekey until the die head has returned to normal position, said mechanismcomprising a locking device for the die head heldout of normal positionwhen the die head is in another position than in its position of rest,and key locking mechanism connected with various keys and adapted to beblocked by such locking mechanism when in such released posi- 26. In anembossing machine, the com bination with embossing dies, of characterkeys for controlling the mutual presentation of the dies and material tobe embossed, mechanism initiated by. such keys for moving the dies toeffect the embossing, a space key, mechanism actuated thereby foroperating the die moving mechanism and for feeding the material at atime when no die is in position to operate, and mechanism for preventingthe actuation of the space key until such actuation would not interferewith the dies.

27. In an embossingmachine, the combination with a movable die carrierhaving a normal position, of character keys for controlling the movementof the.die carrier from its normal position, mechanism initiated by suchkeys for moving the dies to efiect the embossing, a space key whichfeeds the material without causing embossing, mechanism for returningthe die head to normal position and mechanism for preventing theactuation of the space key until the die head has returned to normalposition. 28. The combination of an intermittently movable die headhaving a position of rest, a keyboard for controlling the activeposition of the die head, and mechanism for preventing the actuation ofa subsequent key of the keyboard comprising a locking device for the diehead held out of normal position when the die head is in another sitionthan in its position of rest, and l e lever locking mechanism connectedwit various keys and adapted to be blocked by such locking mechanismwhen in such released position.

In testimony whereof, I hereuntoafiix my signature.

PETER M. coLoUHoUN.

